1.4 KiB
keyboard
The keyboard module provides support for reading keypresses from the keyboard.
Not supported on all targets.
byte readkey()
Waits for and reads a single keypress.
The returning values may vary between platforms:
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letters may be uppercase or lowercase
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modifier keys may be applied or ignored
Available for: Commodore 64 (requires KERNAL), Commodore 16 or Plus/4 (requires KERNAL), Commodore 128 (requires KERNAL), VIC 20 (requires KERNAL), Atari, Amstrad CPC, ZX Spectrum, NEC PC-88.
const byte KEY_ENTER
Key code for the Enter/Return key. Usually 13, but not always.
err
enum error_number
Standard error codes. All codes other than err_ok suggest that the last operation failed.
error_number errno
The result of the last operation.
random
A simple and reasonably fast random number generator. Not suitable for cryptographic or simulation uses.
word rand_seed
Random number generator state.
byte rand()
Get a random byte (0–255) and update the state of the generator.
void init_rand_seed()
Initializes the random number generator state. This may take a long time, even several frames, depending on the target.
Current implementation:
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On C64, spends two frames reading noise data from the SID chip.
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On Z80, reads the refresh register.
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On all other targets, sets the seed to 1.